The present invention relates to a starting assist system capable of improving the starting performance of Diesel engines.
In the Diesel engine, the ignition and burning of fuel are effected by injecting the fuel into the air heated to a high temperature by adiabatic compression, so that when particularly the cold engine (at ambient air temperatures of below 0.degree. C.) is cranked for starting, the temperature of the adiabatically compressed air is low and the ignition of the fuel is deteriorated, thus making it difficult to start the engine without any starting assist means.
Known in the art are starting assist means of the type employing glow plugs which are inserted into the respective precombustion chambers. This means is so designed that the glow plug which is a type of electric heater is heated red hot by supplying current to it and atomized fuel is directed against the red-hot glow plug to facilitate the ignition of the fuel. In this way, the low adiabatic compression temperatures are made up by the heat generation of the glow plug.
A disadvantage of this type of known means is that the time required for heating the glow plug red hot ranges from about 15 to 30 seconds, that the operation is complicated due to the necessity to effect the preheating prior to the cranking and that the time required to start the engine is also long. There is another disadvantage that even a trivial erroneous operation tends to cause troubles such as rundown battery or engine starting failure.